This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. The goal of this proposal is to evaluate the potential of monkey pluripotent stem cells to contribute to the female germ cell lineage, and to explore the feasibility of deriving functional oocytes suitable for use in assisted reproductive technologies. Our main hypothesis is that primate pluripotent stem cells derived from fertilized embryos, experimentally reprogrammed by somatic cell nuclear transfer or direct reprogramming (iPS) approaches are capable of forming female germ cells and gametes upon spontaneous or directed differentiation. We produced GFP knock-in monkey ESC line under the control of germ cell specific promoters: OCT4 and VASA. These cell lines should aid in identification of germ cells during differentiation of ESCs.